Study guides

Study Guide for part 3/3 of class

Study Guide for part 2/3 of class

Study Guide for part 1/3 of class

Spring 2018 Exam retake study guides
1.1 Its estimated that greater than 7.442 billion people live on Earth right now! Earth is thought to max out at 11 billion people based on current technology… LA will be a lot more crowded!

1.2 Right now 6 people live off Earth, the key point of this question is that despite our dreams of Mars and living in space, Earth is pretty hard (and outrageously expensive) to escape. Just look at the moon, its been trying to escape Earth for 3 billion years!

1.3 The sky is blue because air molecules scatter blue wavelengths of light.

1.4 Oxygen is the most common element on Earth. Its in our air, its in our water (H2O), and its in almost all of our rock (SiO2)

1.5 Most of the oxygen that we breath is recycled CO2, which was recycled in Earth's oceans, by the abundance of marine life that lives there.

1.6 The ozone hole over Antarctica is entirely unrelated to global warming. It was caused by CFCs (not CO2 or methane emissions), and unlike global warming, the whole world came together and stopped the creation of CFCs to protect our atmosphere.

1.7 Over the past 100 years, sea-level has risen the most because of a small increase in the temperature of the ocean.

1.8 Earth is currently in a cold period, relative to the abundance of evidence which indicates past global and local temperatures. Most important about this fact, is humans have only become an abundant organism during this cold period.

1.9 If it melts and cools down again, Valentines day chocolate is not going to change into a slide of pizza or a slice of pizza.

2.1 As discussed in class thermodynamics is a useful way of looking at geology. Thermodynamics is concerned with three main forces. Thermodynamics is concerned with Pressure, Temperature, and Chemical Composition.

2.2 Diamonds and Graphite are formed at very different temperatures and pressures, but have exactly the same compositions (they are both carbon). It’s the different crystal structure (a different arrangement of the same atoms) that causes diamonds to be so strong, and graphite to be so weak.

2.3 Scientists should always share their results, even if their hypothesis was proven wrong, the results are still useful for other scientists

2.4 Plankton that died during the time of the dinosaurs is responsible for our current petroleum oil resources.

2.5 Oil sands have high environmental and economic costs. The process requires large amounts of energy to unearth, move, and refine the sands. The process also exposes the workers, the surrounding environment, and the watershed to petroleum products at a higher rate than occurs naturally.

2.6 Modern mining is defined by very powerful machinery which can relocate and process an immense amount of rock material.

2.7 Oil is less dense than rocks and water, and if given enough time tends to floats upward from the source rock until it is either trapped or reaches the atmosphere (which is lighter than the oil, so the oil stops floating up).

3.1 Name two elements which formed shortly after the big bang: Li, He, Be and H. H and He are still the most common elements in the universe (and in our solar system)

3.2 The universe is thought to be around 13.4 billion years old. That’s our best guess right now, but the number has been floating around between 12 to 15 billion years.

3.3 The most common type of minerals on Earth are silicates.

3.4 Being a scientist means using the scientific method, and or deductive, inductive, and abductive reasoning to state arguments based on data or data based theories; anyone can be a “scientist” as long as they use this method. The metric system is just one way of thinking about the world, but is not the only way, and science does not require that you use the metric system.

3.5 Crystalline structure are highly ordered, meaning that they are made up of repeating patterns.

3.6 In most all minerals and almost all of geology, electronic charges in minerals balance out to be 0.

3.7 A silicon tetrahedron is composed of 4 oxygen atoms in a pyramid shape, and one silicon atom inside the pyramid.

3.8 In geology we are primarily concerned with the following phases of matter Gas, Solid, and Liquid. There is a fourth phase of matter (Plasma) but is not too important for our class.

3.9 Coal cannot be a mineral because it is: Not inorganic, Not crystalline, Does not have a definitive chemical composition.

3.10 Abductive reasoning uses incomplete evidence to determine the most likely case.

4.1 The more a silicon tetrahedron shares its charges with other silicon tetrahedron, the less it needs to balance its charge with other metals. Minerals with low amounts of silicon tetrahedron need more metals to balance their charges.

4.2 When magma or lava is cooled exceptionally fast it will form a glass (also known as an amorphous solid).

4.3 The heat inside our earth is powered by radioactive decay of unstable elements.

4.4 Water freezes into “Ice” and alcohol freezes into a solid crystal of alcohol. This same effect is the reason why we have crystals of specific minerals in rocks.

4.5 The electron cloud is 99% or more by volume of the atom.

4.6 Iron is in Earths core because it is heavier than the rest of the Earth and sunk to the bottom

4.7 Humans have only dug about 12 km into the Earth.

4.8 The composition, arrangement, charge and bonding of atoms determines the inside shape of a mineral.

5.1a Faster cooling rocks take a better “picture” of the paleo magnetism

5.1b Rocks higher in iron (mafic rocks) have lower silica and give a better paleomagnetism readings.

5.1c Rocks higher in iron (mafic rocks) have lower silica and give a better paleomagnetism readings.

5.2 The majority of the rocks that make up the earth are igneous rocks with a mafic composition.

5.3 The majority of the rocks on Earth’s surface are sedimentary rocks.

5.4 The outer core is responsible for Earth’s protective magnetic field.

5.5 shape of the continents, location of paleo environments, location of fossils, the location of rock types, the movement of the poles, the discovery of spreading ridges and seafloor textures are all piece of evidence for seafloor spreading.

5.6 A spreading ridge is located where the paleomagnetism mirrors itself.

5.7 A paleomagnetism time sequence looks like ½ of the paleo magnetism seen near a spreading ridge, and works its way further back in time.

Midterm 6 - large exam, no retakes

7.1 Anything that is breaking rocks into smaller pieces by pushing on them is mechanical weathering.

7.2 The act of moving sediment by gravity, wind, water, or ice, is called transportation.

7.3 Deposition is when sediment is left in a new place.

7.4 Lithification is the step of cementing and compacting sediment into a sedimentary rock.

7.5 Anything that is dissolving or reacting (chemically, i.e. bubbles) with a rock is chemical weathering.

7.6 Erosion is the act of moving the weathered rock material off of the rock and into the transportation step. After erosion the rock material is called “sediment”.

7.7 Rocks that form by precipitating from water are chemical sedimentary rocks.

7.8 Rocks that are formed by living organisms (but not the organic (carbon) part of the organism) are biochemical sedimentary rocks.

7.9 Rocks that are formed of the organic carbon part of dead plants and animals is organic sedimentary rocks

7.10 Clastic sedimentary rocks are made of smaller pieces of other rocks.

8.1 Rounded sand grains imply that the sediment (the sand) has been rolling across the earth for a while. These grains start out as sharp edged quartz grains, but get chipped and rounded as they move around the earth.

8.2 The hydrolysis reaction (CaSiO3 + 2CO2 + 2H2O = CaCO3 + SiO2 + CO2 + 2H2O) Destroys silicate rocks while removing CO2 from the atmosphere.

8.3 The hydrolysis reaction (above) is one type of chemical weathering. Acids dissolving rocks (caused by acid rain or pollutants) is another type of chemical weathering

8.4 Sedimentary rocks are typically formed in FLAT and LARGE sheets.

8.5 Contact metamorphism is caused by rocks being heated up from nearby igneous rocks and intrusions

8.6 Limestone is turned into marble when metamorphosed by heat.

8.7 During metamorphism, the grains or crystals inside the rock will grow larger.

8.8 Foliated rocks have a flat (page like) leaf texture. They don’t actually look like leaves, but often have many tiny flat minerals which are flat like leaves or pages are.

8.9 Regional metamorphism will result in the foliated texture.

8.10 Unequal pressure is called “stress”. There are three types: compression,. Tension, and shear.

8.11 There is NO melting during the formation of metamorphic rocks.

Midterm 9 - coming soon!

10.1 Academic references typically inclue the Title, Authors, Year, and Publishing company

10.2 Everyone was able to give a sufficient summary of their paper.

10.3 The title SHOULD be a useful and descriptive introduction to the paper. If the paper talks about things that are not in the title you are doing the scientific community a disservice.

10.4 A fault that has vertical offset, where the foot wall has been raised above the hanging wall is a Normal fault.

10.5a A strike slip fault has no vertical offset, only horizontal offset (movement)

10. 5b A strike slip fault can be further classified by the direction the opposite side of the fault moves (either left or right)

11.1 Yellow layer is the oldest, since it was located on the bottom.

11.2 The youngest layer was a dike that cut though everything else.

11.3 A disconformity is when a layer of the rock is missing

11.4 A crack with no offset is called a joint. If there is offset (the rocks have moved) it would be called a fault.

11.5 The polished surfaces on rocks are called slickensides.

11.6 A cold temperatures brittle deformation is more likely to occur.

11.7 Ductile deformation will occur at high pressures.

11.8 Isostasy is the principle of buoyancy (the iceberg effect)

11.9 Stretching rocks will lower their pressure and will tend to cause them to exhibit brittle deformation

11.10 The rocks displayed xenoliths, which would allow us to conclude that the xenoliths were older than the rocks that were surrounding the xenolith. The relative rocks ages could then be listed.

12.6A Big picture of rock cycle (Magma, Igneous rocks, Sediment, Sedimentary rocks, Metamorphic rocks)

12.6B First level of details on rock cycle (example: metamorphic rocks are broken down into foliated and non-foliated rocks based on how much stress they are formed under)

12.6C Low level details of rock cycle (ecample: metamorphic rocks can be broken down into high and low grade metamorphic rocks)

Midterm 13 - large exam, no retakes

14.1 and 11.2 Mechanical weathering driven by glaciers dragging rocks across other rocks dominates in glacial environments

14.3 Continental glaciers cover entire continents such as Greenland or Antarctica.

14.4 Polar glaciers have much colder temperatures (i.e. -15 C)

14.5 Temperature glaciers have temperatures near the freezing point (0 C)

14.6 Alpine glaciers are found in alpine (mountain) environments.

14.7 Tidewater glaciers are those glaciers which end at the ocean.

14.8 Much like streams, glaciers grow together instead of splitting apart. The direction of a glacier can be inferred by median moraines.

14.9 Median moraines are the long brown stripes in the middle of glaciers

14.10 End moraines form at the end of glaciers by their deposits. This can be caused by a glacier being he same length for many years, or by a bunch of glacial material being pushed together on one year. Regardless glacial moraines.

14.11 Striations are produced by rocks under the ice being dragged across other the bed rocks.

14.12 Striations are the names for the scratch marks as described above.

14.13 Isostatic change was the result of the picture. Points were given for thought out ideas, instead of for correctness.

14.14 River valleys look like "V"s glacial valleys look like "U"s.

14.15 River erosion takes place only at the bottom of the river.

14.16 Glacial erosion is spread across the glacial walls and the bottom of the glacier

14.17 rivers have capacity (how much sediment) and competence (how large of sediment). Capacity is determined by how much water is moving (volume). Competence is determined by how fast the water is moving (velocity).

14.18 For a slot canyon, hard (strong) rocks are needed so that the walls do not erode into the channel the river has cut.

Midterm 15: Points were given for serious answers. Answers which were undescriptive or silly were not given points.

16.1 Caves form in limestone or marble.

16.2 Karst topography is very bumpy texture formed after caves collapse.

16.3 As water infiltrates it goes straight down

16.4 If the water table is on a slope, the water will flow down the slope.

16.5 Water will flow across the water table fastest.

16.6 When sink holes occur, this is mechanical weathering as the roof of a cave collapses.

16.7 Draw down happens when too much water is pumped too quickly form a well.

16.8 Acidic water becomes more neutral when it dissolves carbonate rock.

16.9 Rocks with high porosity will have many holes in them.

16.10 Rocks with high permeability will have cracks or pathways all the way though the rock.

17.1a Mass wasting from slowest to fastest: Creep, Slumping, Debris Flow, Rock-fall or Avalanche.

17.1b A debris flow is slower moving than a rockfall or avalanche (which are at the same faster speed)

17.1c A debris flow is faster than creep and slumping.

17.2a Bent trees are evidence of creep.

17.2b A cloud of dust might apear after a rockfall.

17.2c If covered by snow from an avalanche, you may see tree tops or branches sticking out of the snow.

17.2d A scarp will be formed during slumping events.

17.2e Sand and rocks mixed together with trees is likely evidence of a debris flow.

17.3 Bolts, terraces, riprap, netting, and retaining walls all can help a hillside resist mass wasting.

17.4 Volcanos can cause Lahars, lavaflows, pyroclastic flows, dangerous gasses, and ash; all of which are hazards to humans.